Supriyo Datta

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Numerical simulations are used to guide the development of a simple analytical theory for ballistic field-effect transistors. When two-dimensional (2-D) electrostatic effects are small (and when the insulator capacitance is much less than the semiconductor (quantum) capacitance), the model reduces to Natori’s theory of the ballistic MOSFET. The model also(More)
The possible use of spin rather than charge as a state variable in devices for processing and storing information has been widely discussed, because it could allow low-power operation and might also have applications in quantum computing. However, spin-based experiments and proposals for logic applications typically use spin only as an internal variable,(More)
The non-equilibrium Green’s function (NEGF) formalism provides a sound conceptual basis for the devlopment of atomic-level quantum mechanical simulators that will be needed for nanoscale devices of the future. However, this formalism is based on concepts that are unfamiliar to most device physicists and chemists and as such remains relatively obscure. In(More)
It is well-known that conventional field effect transistors (FETs) require a change in the channel potential of at least 60 mV at 300 K to effect a change in the current by a factor of 10, and this minimum subthreshold slope S puts a fundamental lower limit on the operating voltage and hence the power dissipation in standard FET-based switches. Here, we(More)
A simple model for ballistic nanotransistors, which extends previous work by treating both the charge control and the quantum capacitance limits of MOSFET-like transistors, is presented. We apply this new model to MOSFET-like carbon nanotube FETs (CNTFETs) and to MOSFETs at the scaling limit. The device physics for operation at ballistic and quantum(More)
The performance limits of carbon nanotube field-effect transistors ~CNTFETs! are examined theoretically by extending a one-dimensional treatment used for silicon metal–oxide– semiconductor field-effect transistors ~MOSFETs!. Compared to ballistic MOSFETs, ballistic CNTFETs show similar I – V characteristics but the channel conductance is quantized. For(More)
Carbon nanotube metal–insulator–semiconductor capacitors are examined theoretically. For the densely packed array of nanotubes on a planar insulator, the capacitance per tube is reduced due to the screening of the charge on the gate plane by the neighboring nanotubes. In contrast to the silicon metal–oxide–semiconductor capacitors, the calculated C – V(More)
We performed a comprehensive scaling study of Schottky barrier carbon nanotube transistors using self-consistent, atomistic scale simulations. We restrict our attention to Schottky barrier carbon nanotube FETs whose metal source/drain is attached to an intrinsic carbon nanotube channel. Ambipolar conduction is found to be an important factor that must be(More)